GB2443538A

GB2443538A - Mounting cutter blades

Info

Publication number: GB2443538A
Application number: GB0721227A
Authority: GB
Inventors: Robin Donald Stimson
Original assignee: SABRE PLASTICS TOOLING Ltd
Current assignee: SABRE PLASTICS TOOLING Ltd
Priority date: 2006-11-01
Filing date: 2007-10-30
Publication date: 2008-05-07
Anticipated expiration: 2027-10-30
Also published as: GB2443538B; GB0621730D0; GB0721227D0

Abstract

An arrangement for enabling the mounting of a cutter blade 8 (particularly a vibrating blade) to a machine/apparatus by means of a threaded stud 9 having a diameter greater than the thickness of the cutter blade. An attachment member 11 extends from an end of the stud 9 with a thickness less than the stud diameter and comprises a stem part 15 extending axially from the stud and laterally extending diverging portions 16. The member 11 locates in a correspondingly shaped recess/cut-out 12 in the edge of the blade 8 and can also have a bar-like portion 18 at the end of each portion 16.

Description

S 2443538 llvfPROVEMEfS IN VIBRATING ARTICLES In various industrial,

commercial, and other activities it is known to make use of vibration arising. fram the use of ultrasonic waves in conj.unction with cutting displacements of a cutter blade..

In practise, the ultrasonicfrequencjes used run into several thousands per second.

In relation to the use of material cutting blades it has been found that often when cutting with a reciprocating action materials that are not rigid and or are inherently sticky the cutter blade tends to become at least partially coated with a sticky deposit with the result that the blade no longer effects a clean cut but introduces a tearing C..I. . . V, 3. .L nw 3U411 a, cream coated cakes and so forth.

V.Ln such*eases it has b Vfe4.that 4f..th subjected to ultrasonic vibrajiori the tendency for. the blade to. be so. coated. is. reduced..

1 i. .,. V L.) - f j9r.. rI WU ç*j V intensive usage and are thus subjected to considerable wear. Such wear not infrequently results in the cutting edge of the blade becoming pitted, chipped, together with the turning over of the cutting edge.. When such a situation arises it is eai--pce e.ba4e. This.aa'y -g-a 4poary shutting down of the machine arid a consequential loss of cutting production, in order to reduce the shut down period as much as possible it is important that cutter blades should be readily removable from the machine to which it is mounted and c-en.s. eadi: a'e to the r+ac-hiie.

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it 1!1 tiiu uc wi*ci uuj uat taac uiauc wiaii UHI fcZuaay a1uauiç associated machine a blade must be so mounted that whilst in use it it does not readily detach from its mountings as a result of the combined effects of cutting usage and the application thereto of the ultrasonic vibrations Iq%Tj the-presently kiovwcutting machines it is theon ntional practice-t provide-the b[a1e with a mounting stud that screws into a threaded recess provirled for the mounting of the blade.

Expertence has' shoyt that the cutter blade needs' to have a tblckness' at the position where the cutter blade connects with the stud that is at [east twice the diameter of the I Ostud. so that a stud receiving bore in the blade is surrounded with an mechanically adequate wall thickness of the cutter blade at the position for the mounting of the stud.

Furthermore as a result of practical experience it is well known that the material of the blade has to have considerable resistance to wear, the capability of being able to 15provide a long lasting sharp edge and the ability of accept the usage of high frequency ultrasonic wave energy.

Thus in order to maximise the use of the ultrasonically energised blades it is the conventional practice to make use of materials that have at least the above range of properties. One such materia is titanium.

Titanium is a very very expensive material and as a consequence of the requirement for the above mentioned wall thickness cutter blades have been historically machined from a billet/block of titanium initially having a minimum thickness of at least twice the diameter of the required mounting stud diameter. This necessitates in order to produce from the billet/block a blade cutting region of a suitable 25thjckness from the billet/block having a sufficient thickness ie, some 10 to 15% of the initial' billet' thickness machining away some 85' to 90% of the original billet/block thickness..

Furthermore, it should be noted that as a consequence of the use of ultrasonic energy it is important the zones of changes of thickness in the billet to obtain the appropriate blade formation must be represented by smooth thickness changes and the avoidance where of any sharp edges/corners that could result in ultrasonic energy hot spots which could result in considerably shortening the working life of the cutting blade.

OBJECT OF HE INVENTION

101t is an object of the invention to provide a cutter blade construction and mounting therefore by means of which the extent of machining of the material from a billet/block of cutter blade forming material is greatly reduced.

STATEMENTS OF THE INVENTION

Broadly, according to a first aspect of the invention there is provided an arrangement 1 5 for enabling the operational mounting of a cutter blade to a machine/appara5 by means of a threaded stud having a diameter greater than the thickness of the cutter blade, the arrangement including a shaped blade attachment member having a 4hI.a, l.n,,, h..... +i, C+1.a,.+.a,l +.. *ln$ .1 *n...A.,n,$s +ha,+ shaped attachment member that is adapted to engage in a correspondingly shaped recess/cut-out provided in an edge region of the blade.

In. thnn ohirws,' hlo,'lna HQf'my mp,v,hr *nrnI,,,4n. on s jn %L%#a %#% ss.)q.n tat.,_fl. *tt.finna1j,,. tlas.%.,# n. ass_s aa_.., Ian.

elongate stem part that extends in in axial prolongation of the stud, and laterally extending portions lying in the plane of the stem part serving to assist in anchoring the attachment when mounted to the blade. S -4-

In particular the laterally extending portions each includes a main part laterally projecting from the stem and a cross piece at the free end of each main part, with each cross piece in the plane of and perpendicular to the associated main part.

According a a further aspect of the invention there is provided an arrangement for enabling the operational mounting of a cutter blade to a machine/apparatus by means of a threaded stud having a diameter greater than the thickness of the cutter blade, the threaded stud having an attachment member extending from an end thereof with a thickness less than the diameter of the stud, and including a stem extending in axial prolongation of the stud, and laterally extending portions Eying in the plane of the stem part that diverge outwardly relative to the length of the stem that assist in anchoring the attachment when mounted to the blade..

A further aspect of the invention provides a method of mounting a cutter blade, to a machine by means of a connecting stud or the like, the blade having a thickness that is less than the diameter of the stud or the like, including the steps of providing a shaped recess/cut.out in an edge region of the blade that is remote from the actual cutting edge of the blade,and forming at an end region of the stud or the like a projection that is engageable in said recess/cut-out According to a further aspect of the invention there is provided a reciprocatable cutter blade construction including a connecting stud or the like, and having a thickness less than the diameter of the stud or the like, including a shaped recess/cut-out in an edge region of the blade that is remote from the actual cutting edge of the blade, said stud connecting with the blade by means of a correspondingly shaped projection that is engageabje in said shaped recess.

In a preferred arrangement the shaping of the recess and the projections is such that they are interengageable with a locking action that is such as to act in such manner as to maintain the engagement throughout cutting action of the blade. S -5-

BRIEF DESCRiPTIoJ OF Ti-IF DRAWINGS

For a better understanding of the invention and to show how to carry the same into effect reference willi now be made to the accompanying drawings in which lim,rp 1 v4 f0 l-rw'Iim v.Ilftar.i,'ij-J ifc i;vji,jn Sb4a te S#A SI%4 V k%,#VV #4 te S%11tF VT St %#tSV. 5 tVS..%4 tS*S%a I IJ St &%I te*ttSSLb Figure 2 illustrates to a larger scale a detail of the blade shown in Figure 1, only a fragmentary portion of the blade being illustrated; Figure 3 is a perspective view of a portion of a cutter blade and its mounting arrangements in accordance with the concepts of the present invention; and Figure 4 is a schematic perspective view of the relationship between a mounting attachment of a stud of the invention and a fragrnentally illustrated blade..

DETAILED DESCPJPTJON OF THE FIGURES OF THE DRAWiNGS.

Referring now to Figures 1 and 2 these Figures as mentioned illustrates a cutter blade 1 construction as now conventionally used in the cutting of materials of a sticky or squashy nature such as cream covered cakes, pizzas etc. The cutter blade 1 is formed from a rectangular billet/block of a material suitable for the cutting requirements, in the embodiment illustrated the cutter blade is formed from titanium.

The cutter blade I is conventionally mounted, to a machine/apparatus (not shown) that causes the blade to undergo its cutting strokes whilst being subjected to ultrasonic vibration at frequencies of the order of 20000 cycles per second, by means of a screwed stud 2. which engages with a threaded blade mounting bore (not shown) of the apparatus/machine * In practice, with this mode of mounting it is important to ensure that the thickness of blade material surrounding the stud 2 is fully adequate to ensure a firm and secure mounting of the stud 2 into the blade 1.

c' hsn n t, th rf hJ,l :;:: i::::; z; the;C;::o;; ::r:;T:;: a bore; provided in the bade I should be at least twice the diameter of the stud 2 so that the wall thickness 3 (across the thickjiess of the blade) of the threaded bore formed in the cutter blade for receiving the stud is at least equal to one half of the diameter of the stud.

As a result in order to produce from the originating titanium billet/block an acceptable thickness for the actual cutting region 4 of the cutter blade 1 leading to the actual cutting edge 5 a substantial amount of material has to be removed from the originating titanium billet/block...

As may be seen from the Figures 1 the blade originating billet/block thickness as represented in the vicinity of the stud 2 is thus very greatly reduced in the thickness in two stages from its initial thickness through an intermediate stage 6 to the thickness of the main cutting body region 7 of the cutter blade to a tapered cutting edge region 8 terminating at the actual cutting edge 5.

In practice, this overall thickness reduction involves the removal of some 85 to 90% of the originating titanium billet/block..

It will be noted that the there is a smooth transition at the locations of the thickness reductions of the billet/block to provide the main cutting body region 7 1 -7-With a view to avoiding so-called hot spots arising from the use of the ultrasonic energy slots (not shown) are provided in the thicket regions of the blade (i.e., the intermediate stage 6 and original thickness regions 3 of the cutter blade 1 nn,i, in Tiiyro thc' ,nttrn. kl.4 Q nnrywir.f,mn tI, &s&sn LI S s * tj A&fl%4fl fl,.J *4 ** **4% 4.1 L*jj f14J4 %**UAb of the present invention.. As will be noted the cutter blade 8 in the form of a rectangular blank cut from a sheet of titanium having an initial thickness substantially equal to the required operational thickness, for the cutter regions 9 of the blade. It will be understood that a small amount of material would be inevitably removed if any machining is required to ensure that the thickness of the blade is uniform at a value required for a particular cutting application and for the purposes of polishing and sharpening the blade for use.

The cutter blade 8 of the Invention is intended to be mounted to the associated machine by means of a threaded stud 9 that has a diameter that is the same as that shown in Figures 1 and 2 i.e., as is necessary to enable t he blade to be mounted to its 1 associated machine.

It will be noted that the blade 8 is of an uniform thickness throughout and that its thickness is considerably less than the diameter of the conventionally used stud 2 and thus the stud 9..

In order to enable the attachment of a stud 9 having a greater diameter than the thickness of the material forming the blade one end JO of the stud 9 is provided as indicated in Figure 4 with a shaped blade mounting attachment member 11 that is engageable with a correspondingly shaped cut-out/recess 12 provided in centre of the edge 13 of the cutter blade 8 that is opposite to the cutting edge 14 of the blade As seen in Figures 4 and 5, the shaped attachment member 11 at the end of the stud 9 includes a stem part 15 that is inline with the axis of the stud 9, a pair of arms 16

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(ntIP)r4J1 *p crr,ry, th 1 7 r' th. c'fyp rILrt 1 ç LIP.fl *aa I_as) .#sla) W I.tS I I_lA SS5 ass jj *Js*JtAs4.4._,s. at I_Fits I_i LI_I 5 %ILI 115%_a S $ I_PS SILL! SIt%$tfl 5 of the stud 9. A bar like region 18 with smoothly rounded ends 19 is provided at the free end of each arm 16 with each said bar like region 18 being arranged in the plane of and perpendicular to the associated arm 16.

The recess/cut out 12 in the blade is of the same shape as the attachment of the stud and thus involves the equivalents of the parts of the attachment member II.

Furthermore, the recess/cut-out 12 and is of such dimensions that the attachment member 11 can be entered into the slot/cut- ut without causing any distortion of the 1 2 Th. 1 1 ,-mh, r, ,wacfI,I_,, k, ,, 5J554%5%.. J S ILL! tSttaL!sasn_,115 S a 515515 5 I_I.tsslsaass ISA ALAs) 111 f.flflJsLAt_P.s LI) Sass 55.$flA welding or like operation.

The thickness of the stud attachment member 11 in relation to that of the blade 8 can be such that when fitted its outer surfaces are slightly proud or flush with adjacent surface(s) of the blade. In other words, the surfaces of the stem part 15 and its arms 16 and bar regions 18 are slightly proud of the adjacent surfaces of the cuter blade.

8 Alternatively the attachment member surfaces can be flush with the adjacent surfaces of the blade 8.

It has been found that the shaping of the attachment member 11 as depicted in the Figure 3 has the effect of producing as a result of the engagement in the opening/recess 12 in the blade 8 a locking action is produced an anchoring/tightening the stud on the mounting bore therefore to the associated machine (not shown). This c c *r o'$ n.nnar +r m,.t,,,., th ra-i,,,r .j r,y, tS%#5551L. 5..? .J%451 lasJ SI_P 5*515 Las JI.4%?Ls aAs.aasg....s 551 SI_I LtttSIststss 553%! 5 issj5*sa 51%5 Lana.

throughout cutting action of the blade.

In order to avoid the possibility of energy hot spots being produced in the blade when in use the latter can be provided with conventionally used slots (not shown) In the present embodiment a pair of parallel cuts 15 are formed in the blade.

Claims

CL&IMS 1 A r +Is r niciiiif1i.1-p f"f$ kI.,1S +, S. S $41 t$S S t54b15"

S$JS tSta$4aSj tflS%# $4fJI L4$S$4*S$4.4 uS$1 tSSflSS1 $11 $4 %1tt$1n t#i$4$4$1 $$J $4 machine/apparatus by means of a threaded stud having a diameter greater than the thickness of the cutter blade, the arrangement including a shaped blade attachment member having a thickness less than the diameter of the stud to which it is attached and c,,,1, *h. t tkae Qhu*r,.1 ii, & .J$4S, t1S t*S$1 aSL$41j$1$1 L$4$1. LL1I$15 St 511 SISLI$1n S1S&4$ SI * $1flS%4$1 55 correspondin[y shaped recess/cut-out provided in an edge region of the blade.
2. An arrangement as claimed in claim 1, and wherein the shaped blade attachment member includes an elongate stem part that extends in in axial prolongation of the stud, and laterally extending portions lying in the plane of the stem part serving to assist in anchoring the attachment when mounted to the blade.
3. An arrangement as claimed in claim I or 2, and wherein the main parts of the laterally portions diverge outwardly relative to the length of the stem.
4. An arrangement as claimed in claim 3, and wherein the laterally extending portions each includes a main part laterally projecting from the stem and a cross piece at the free end of each main part.
5. An arrangement as claimed in claim 4. and each cross piece is arranged in the plane of and perpendicular to the associated main part.
6. An arrangement as claim in claim 4 or 5, and wherein the each cross piece has smoothly rounded ends.
7 6, rr)n4,m,r,t)C' II 5)tV,* flf f'I')IW,(' 1 tf$ sv,,rl i,hseri tk5e t'h1e,4 S 455 5 fl*asa. %saa %4&_F $1Stta 5SS$1 S t.5_7 a S 145 55141 4 t% $4, $45145 51451 recess or Cut-out is formed in the blade at the centre of the edge region of the blade that is opposite to the blade cutting edge

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8. An arrangement as claimed in any one of claims I to 7, and wherein when the element is engaged with the recess in the blade the stem and the laterally extending positions are slightly proud of the adjacent surfaces of the cuter blade.
0 e,,,, 4 t, Q ri- fh a. j La L.a ga a, ls. ALA a%. oAALasAsb of the main pats and the cross pieces are such that they are engageable in the recess/cut-out with a locking action that is such as to act in such manner as to maintain the engagement throughout cutting action of the blade.
10. An arrangement for enabling the operational mounting of a cutter blade to a machine/apparas by means of a threaded stud having a diameter greater than the thickness of the cutter blade, the threaded stud having an attachment member extending from an end thereof with a thickness less than the diameter of the stud, oy,,4 o (t.a,.ri, oi-,,J, the.. c'ti,,4 o,,,-1 LaJ * La LLAx S LI tfl4j fJS SLfl4.,fl ttL LPSL4 LaSS%a AL4LA SAl) extending portions lying in the plane of the stem part that diverge outwardly relative to the length of the stem that assist in anchoring the attachment when mounted to the blade..
11. An arrangement for enabling the operational mounting of a cutter blade to a machine/apparatus for operationally displacing the blade, constructed and arranged to operate substantially as herein before described with reference to Figures 3 and 4 of the accompanying drawings.
12. A method of mounting a cutter blade, to a machine by means of a connecting stud or the like, the blade having a thickness that is less than the diameter of the stud or the like, including the steps of providing a shaped recess/cutout in an edge region of the blade that is remote from the actual cutting edge of the blade,and forming at an end region of the stud or the like a projection that is engageable in said recess/cut-out

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13. A method as claimed in claim 11, in which the recess includes a main section defining the axial position of the stud or the like, and oppositely extending arm members that serve to stabilise/anchor the stud in its operative position in the edge region.